CN1314990A - Thin film strain sensors based on interferometric optical measurements - Google Patents
Thin film strain sensors based on interferometric optical measurements Download PDFInfo
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- CN1314990A CN1314990A CN99810062A CN99810062A CN1314990A CN 1314990 A CN1314990 A CN 1314990A CN 99810062 A CN99810062 A CN 99810062A CN 99810062 A CN99810062 A CN 99810062A CN 1314990 A CN1314990 A CN 1314990A
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- 239000010409 thin film Substances 0.000 title abstract description 5
- 230000003287 optical effect Effects 0.000 title description 10
- 238000005259 measurement Methods 0.000 title description 5
- 229920001296 polysiloxane Polymers 0.000 claims abstract description 17
- -1 polysiloxane Polymers 0.000 claims abstract description 16
- 239000004642 Polyimide Substances 0.000 claims abstract description 14
- 229920001721 polyimide Polymers 0.000 claims abstract description 14
- 239000002245 particle Substances 0.000 claims abstract description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 claims description 8
- 229920000728 polyester Polymers 0.000 claims description 5
- 239000004743 Polypropylene Substances 0.000 claims description 4
- 239000004809 Teflon Substances 0.000 claims description 4
- 229920006362 Teflon® Polymers 0.000 claims description 4
- HGAZMNJKRQFZKS-UHFFFAOYSA-N chloroethene;ethenyl acetate Chemical compound ClC=C.CC(=O)OC=C HGAZMNJKRQFZKS-UHFFFAOYSA-N 0.000 claims description 4
- 229920000515 polycarbonate Polymers 0.000 claims description 4
- 239000004417 polycarbonate Substances 0.000 claims description 4
- 229920001155 polypropylene Polymers 0.000 claims description 4
- 239000000758 substrate Substances 0.000 abstract description 4
- 238000010276 construction Methods 0.000 abstract description 3
- 239000004065 semiconductor Substances 0.000 abstract description 3
- 239000011521 glass Substances 0.000 abstract description 2
- 230000004044 response Effects 0.000 description 13
- 238000002835 absorbance Methods 0.000 description 6
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 4
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B9/00—Measuring instruments characterised by the use of optical techniques
- G01B9/02—Interferometers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
- Optical Transform (AREA)
Abstract
The invention relates to polymeric/semiconductor thin film strain gauges comprising visible light from spectrometer (10) which is directed onto a thin film passive sensor (12) having a transparent glass substrate (14) and a laminated construction in succession from the substrate (14), of a polyimide layer(18a) a polysiloxane layer (16a) filled with alumina particles, a polyimide layer (18b) and a polysiloxane layer (16b) filled with alumina particles.
Description
Invention field
The present invention relates to polymkeric substance/semiconductive thin film strainometer.
Background technology
Many civil engineerings are configured in and are exposed to nature after the several years, can present fatigue, can lose efficacy once in a while.Sometimes, inefficacy is that disaster causes, as earthquake, wind spout or storm etc.Like this, just require a kind of cheapness that season, environmental change influenced, durable and sensitive strainometer of not being subjected to, in addition, this class sensor should be simple in structure, be convenient to install and be integrated in the modern data communication systems easily.
Here the sensing system of Jie Shiing can monitor the integrality of structure, to guarantee public safety and maintenance.The application scenario of feature comprises the integrality of building, road and bridge.As sensitive element, native system has adopted the optical extensometer of a plurality of cheapnesss, and they are inertia to physical environment, and physical arrangement is firm.Combine with automatic data acquisition and diagnostic analysis program, also can be contained in this class sensor and optical fiber data link thereof on superstructure and the bridge foundation, be contained in the building supporting member, or embed the surface of road and overpass.Only with minimum " health " situation that manually can automatically monitor and assess this class formation and surface.Aspect reparation required after daily maintenance requirement of assessment or potential disastrous load, detailed application message also had certain value.
Summary of the invention
The sensitivity of sensor has technology different with passivity and source.Present resistance strain sensor, its coefficient of strain (measuring of sensitivity) is about 1～3, and the coefficient of strain of the sensor that discloses is 200～800 magnitudes.Be difficult to believe that the passive sensor sensor that original technology discloses can be equipped with the storer that does not rely on power supply.
Usually measure strain with semiconductor or thin polymer film.Film is a hierarchy, and every layer of material of analysing the rate of penetrating by difference formed.Because every layer refractive index difference can reflect on each interface or pass through so introduce the light of composite structure, make by interfering to cause measurable absorption to change with the incident light that reflects.The interference degree is responsive to every layer refractive index and thickness, and thickness changes with the external carbuncle that applies, and light absorption variation as a result is relevant with strain, thereby the absorption variation can be used to measure strain.
Here disclose two class interference sensors, i.e. active type and passive.Active sensor is reversible to the response of strain, and promptly along with the variation of stress, absorption changes in reversible and predictable mode.The strain that this class sensor is used for existing on the measurement structure.
Passive sensor has the storer of the maximum strain that a structure lived through.For example, be little surplus value if structure stands big deformation (big strain) back lax, then this large deformation is irreversible.Active sensor is ability energy measurement strain incident when watch-keeping only, and passive sensor is only measured the maximum stress that lives through.If active sensor does not monitor when maximum strain occurring, will can not observe big strain deviation.Passive sensor can address this problem.
In broad terms, the present invention includes the active and passive two class sensors that preferably are applied to same structure, they use the semiconductor or the body plan of polymkeric substance layered material of different refractivity.When refractive index maximum and the number of plies increased, sensitivity just uprised.To add granule to a component layers during body plan passive sensor.
The accompanying drawing summary
Fig. 1 illustrates passive sensor;
Fig. 2 a and 2b illustrate another embodiment of Fig. 1;
Fig. 3 is the optical response plot figure of active sensor;
Fig. 4 is the optical response plot figure of passive sensor; And
Fig. 5 is the optical response plot figure of passive sensor.
The description of preferred embodiment
Can determine strain by measuring incident light with reflectance or transmission.
With reference to the reflective-mode of Fig. 1, be mapped on the film passive sensor 12 from the visible light of spectroscope 10 (as Perkin Elmer Lambda2).Comprise transparent glass substrate 14 on the sensor 12 and begin continuous laminated construction that laminated construction comprises silicone layer 16a, the polyimide layer 18b of polyimide layer 18a, filling alumina particle and the silicone layer 16b of filling alumina particle from substrate 14.Incident beam is perpendicular to sensor surface.Light is collected along the incoming beam path in the photomultiplier detector in the spectroscope 10 20.The thickness range of each layer is 1～20 micron.When making passive sensor, the alumina particle of 50nm is sneaked into silicone layer, its weight accounts for 0.5～10% of polysiloxane general assembly (TW).Make, granule gathers certain (unknown at present) degree.Under stress, some particle of gathering separately loads polymkeric substance between freshly sepd alumina particle.After stress was eliminated, because the intervention of polymkeric substance, particle just can't reassociate.This situation can detect with optical means, because the scale of assembling has been determined the light quantity from sample scattering; Change along with the aggregate size stress, because detecting device is only to very little spatial volume sampling, so the light quantity of directed toward detector changes.Passive sensor need not the energy can realize its memory effect.
With reference to the transmission mode of Fig. 2 a, active sensor as photoconductive tube, is deposited to its outer wall with film 32 (as polysiloxane/polyimide) with kapillary 30 (as internal diameter 0.5mm, external diameter 0.7mm), then these films is coated aluminium 34.Aluminium 34 be used to keep constraining in whole light of managing in 30, and the protection total is avoided the influence of surrounding environment as catoptron.Fiber light source 36 is that the parallel light of 500～1000 is sent into an end of kapillary 30 in the kapillary longitudinal axis with wavelength coverage, and detecting device 38 is collected light at the other end.
In capillary pipe structure, pipe 30 plays waveguide and sensor double action.When unstressed, most of light passes through along pipe, does not have interaction with tube wall.After adding stress, Figure 26 is seen in kapillary 30 bendings, makes a large amount of light import film coating along tube wall.There are two kinds of effects to cause the modulation of output intensity.At first, path has become, and has increased any absorption that takes place, and the increase degree depends on the spring number of times of the absorbance log of pipe wall material and the light of advancing.Secondly, the interference effect of light during by thin layer is still effective, and causes intensity modulation by long or destructive interference mutually, specifically depends on the refractive index of each layer and the optical wavelength of thickness and use.
The layer that respectively replaces must have different refractive indexes, and difference is big more, and the sensor response characteristic is good more.The n=1.6 of polyimide～1.7 (the concrete polyimide, curing characteristics and the supplier that depend on use); The n=1.44 of polysiloxane.Other often has commercially available transparent polymer that tygon, polypropylene, teflon are arranged
, Kynoar, polyester or the like, refractive index is about 1.4, can substitute silicone layer.Polyester or the like, refractive index is about 1.4, can substitute silicone layer.The refractive index and the polyimide of high index of refraction polymkeric substance such as polycarbonate are close.
Preferable sensing system requires near passive and active two kinds of sensors of settling.Passive sensor measure experience but be not the maximum strain skew of of short duration history, the strain that promptly records can be current or former.Therefore, the effect of active sensor is to measure the strain that occurs when measuring.
Can sensor be arranged to a certain structure with the combination technology that contemporary strain transducer uses.Because of sensor is very little, so can measure the stress of flaky material reliably.Light source and detecting device needn't with the sensor setting-in.Utilize suitable optical fiber to connect, the hand-held spectroscope is connected to the input and the output terminal of sensor, can regularly do optical measurement.Like this, for example later spent several days or still can determine the maximum strain that each member experienced in the building after a few week, establishing the security in this building, even if because passive sensor is still keeping this information losing under the situation of the energy in earthquake.Perhaps, can be with the remote sensing strain automatically of the capable net of the light that is connected to big each sensor of number.Yet in disaster accident, optical networking may rupture, and has hindered this operator scheme.The material that uses in the sensor is promptly cheaply durable again.For example, polysiloxane is a kind of market gasket sealer on sale.Capillary structure especially is fit to prolonged application, because can seal whole sensor in case of necessity.So for example if prepare sensor application in rigorous environment such as bridges, whole sensor just can separate with wind and rain, salt fog etc., because any coating that is added in outside the aluminium lamination does not exert an influence to sensor performance.
For example
Fig. 3,4 and 5 has enumerated the response characteristic of sensor.Light source is a tungsten lamp, by four-point bending stress application (seeing ASTM C-1341-97).
Fig. 3 is shown in the response characteristic of two different active strain transducers, and one of them has 12 layers (6 polysiloxane that replaces and polyimide layer), and another has 26 alternating layers.About 10 microns of layer thickness.Monitor the absorbance log relevant with the strain that applies at the 600nm place, the result as shown in the figure.The coefficient of strain is the function of the number of plies, and the interference pattern of response characteristic is described.Moreover the coefficient of strain is very big, than two amounts of general strain ga(u)ge extremely more than.At last, response characteristic is linear, and is reversible in the gamut up to about 2000 μ strain (this is that structure is used the required limit, because at 2000 μ strain places, most of materials exceed its plastic deformation limit).
Fig. 4 illustrates the response characteristic of the passive strainometer of 26 alternating layers.About 10 microns of original thickness.After adding upper stress, response characteristic is similar to active strainometer.Monitor absorbance log at the 600nm place.Yet, when cancellation during stress, respond no longer reversiblely, promptly the 0strain absorbance log depends on the history of sample.For some differently strained skews, this situation is shown in Fig. 4.New strainometer is at the absorption value A=0.73 at 60nm place.After adding 300 μ strain, become A=0.83.In case stress relief is returned 0 μ utrain, and absorbance log is just returned A=0.78, shown in dash line among Fig. 4.Apply any stress, reversibly follow dashed path less than 300 μ strain.Yet if stress surpasses 300 μ strain, the path just is returned among Fig. 4 the solid line shown in the 600 μ strain points.When present cancellation stress, just get new path, shown in dotted line, the new absorbance log up to 0 μ strain place.
Increment between stress deviation increases with stress and reduces (being that passive response is non-property line) continuously, as shown in Figure 5.The coefficient of strain of 12 ply strain meters is little, but has big approaching or linear responding range.26 layers strainometer has the bigger coefficient of strain, but becomes pure non-linear at much smaller maximum stress place.
Foregoing description is limited to specific embodiment of the present invention always, but obviously can do change and revise the present invention, and obtains part or all of advantage of the present invention.Therefore, attached claim is intended to cover all these class changes of practicalness according to the invention and scope and revise.
Claims (16)
1. interference strain-gage pickup comprises:
Supporting member;
Ground floor polymeric material with first refractive index;
Have the second layer polymeric material of second refractive index that is different from first refractive index, the coefficient of strain of sensor is at least 100, and luminous energy and sensor are related, and when sensor was added stress, luminous energy was partially absorbed, and luminous energy changes relevant with the stress that applies.
2. sensor as claimed in claim 1 comprises:
The a plurality of ground floors that replace and the second layer.
3. sensor as claimed in claim 2, wherein the refractive index of ground floor is about 1.6～1.7, and is selected from polyimide and polycarbonate.
4. sensor as claimed in claim 3, wherein ground floor is a polyimide.
5. sensor as claimed in claim 2, wherein the refractive index of the second layer is about 1.4, and is selected from polysiloxane, tygon, polypropylene, teflon
, Kynoar and polyester.
6. sensor as claimed in claim 5, wherein the second layer is a polysiloxane.
7. as claim 4 or 6 described sensors, the thickness in its middle level is about 1～20 micron.
8. sensor as claimed in claim 1 comprises:
The device that sensor is contacted with luminous energy; And
Measure the device that luminous energy changes.
9. sensor as claimed in claim 1, wherein sensor is a kind of passive sensor, one of described layer is equipped with particle.
10. sensor as claimed in claim 9 wherein has a plurality of conclusions of the business first and second layer for relation, and ground floor is selected from polyimide and polycarbonate, and the second layer is selected from polysiloxane, tygon, polypropylene, teflon
, Kynoar and polyester.
11. sensor as claimed in claim 10, wherein ground floor is a polyimide, and the second layer is the polysiloxane that alumina particle is housed.
12. sensor as claimed in claim 9 comprises:
The device that sensor is contacted with luminous energy; And
Measure the device that luminous energy changes.
13. sensor as claimed in claim 1, wherein sensor is a kind of active strainometer, and comprises the tubular support of the ground floor second layer.
14. sensor as claimed in claim 13, wherein the refractive index of ground floor is about 1.6～1.7, and is selected from polyimide and polycarbonate, and wherein the refractive index of the second layer is about 1.4, and is selected from polysiloxane, tygon, polypropylene, teflon
, Kynoar and polyester.
15. sensor as claimed in claim 14, wherein outermost layer aluminising.
16. sensor as claimed in claim 15 comprises:
The device that sensor is contacted with luminous energy; And
The device of measuring light energy variation.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US9798998P | 1998-08-26 | 1998-08-26 | |
| US60/097,989 | 1998-08-26 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1314990A true CN1314990A (en) | 2001-09-26 |
Family
ID=22266087
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN99810062A Pending CN1314990A (en) | 1998-08-26 | 1999-08-25 | Thin film strain sensors based on interferometric optical measurements |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP1135667A1 (en) |
| JP (1) | JP2002523764A (en) |
| KR (1) | KR20010072920A (en) |
| CN (1) | CN1314990A (en) |
| AU (1) | AU745103B2 (en) |
| CA (1) | CA2341166A1 (en) |
| WO (1) | WO2000012960A1 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100442007C (en) * | 2003-08-21 | 2008-12-10 | 台达电子工业股份有限公司 | Method and structure for measuring thin-membrane strain |
| CN101198851B (en) * | 2005-05-25 | 2010-04-14 | 皇家墨尔本理工大学 | Polymeric strain sensor |
| CN101135660B (en) * | 2006-08-28 | 2013-01-23 | 热敏碟公司 | Vapor sensor and materials therefor |
| CN109073499A (en) * | 2016-04-12 | 2018-12-21 | 赛菲斯特弗雷结构技术公司 | For measuring the method and prospecting device of the stress in condensation product structure |
| CN110307921A (en) * | 2019-07-02 | 2019-10-08 | 运城学院 | A kind of pressure sensor |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003025035A2 (en) | 2001-09-14 | 2003-03-27 | Merck Patent Gmbh | Moulded bodies consisting of core-shell particles |
| DE10204339A1 (en) | 2002-02-01 | 2003-08-07 | Merck Patent Gmbh | Strain and compression sensor |
| DE10227071A1 (en) | 2002-06-17 | 2003-12-24 | Merck Patent Gmbh | Composite material containing core-shell particles |
| ITBO20070587A1 (en) * | 2007-08-13 | 2009-02-14 | Portu Goffredo De | METHOD FOR MEASURING VOLTAGES IN A STRUCTURE OR IN A COMPONENT OF A WORKING STRUCTURE |
| WO2016161104A1 (en) | 2015-04-01 | 2016-10-06 | Vayavision, Ltd. | Generating 3-dimensional maps of a scene using passive and active measurements |
| US10445928B2 (en) | 2017-02-11 | 2019-10-15 | Vayavision Ltd. | Method and system for generating multidimensional maps of a scene using a plurality of sensors of various types |
| CA3125618C (en) | 2020-07-21 | 2023-05-23 | Leddartech Inc. | Beam-steering device particularly for lidar systems |
| CA3125716C (en) | 2020-07-21 | 2024-04-09 | Leddartech Inc. | Systems and methods for wide-angle lidar using non-uniform magnification optics |
| WO2022016276A1 (en) | 2020-07-21 | 2022-01-27 | Leddartech Inc. | Beam-steering device particularly for lidar systems |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0224502A (en) * | 1988-07-12 | 1990-01-26 | Dainippon Screen Mfg Co Ltd | Film-thickness measuring method |
-
1999
- 1999-08-25 EP EP99943961A patent/EP1135667A1/en not_active Withdrawn
- 1999-08-25 JP JP2000567901A patent/JP2002523764A/en active Pending
- 1999-08-25 CA CA002341166A patent/CA2341166A1/en not_active Abandoned
- 1999-08-25 AU AU56949/99A patent/AU745103B2/en not_active Ceased
- 1999-08-25 CN CN99810062A patent/CN1314990A/en active Pending
- 1999-08-25 KR KR1020017002341A patent/KR20010072920A/en not_active Application Discontinuation
- 1999-08-25 WO PCT/US1999/019601 patent/WO2000012960A1/en not_active Application Discontinuation
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100442007C (en) * | 2003-08-21 | 2008-12-10 | 台达电子工业股份有限公司 | Method and structure for measuring thin-membrane strain |
| CN101198851B (en) * | 2005-05-25 | 2010-04-14 | 皇家墨尔本理工大学 | Polymeric strain sensor |
| CN101135660B (en) * | 2006-08-28 | 2013-01-23 | 热敏碟公司 | Vapor sensor and materials therefor |
| CN109073499A (en) * | 2016-04-12 | 2018-12-21 | 赛菲斯特弗雷结构技术公司 | For measuring the method and prospecting device of the stress in condensation product structure |
| CN110307921A (en) * | 2019-07-02 | 2019-10-08 | 运城学院 | A kind of pressure sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| EP1135667A1 (en) | 2001-09-26 |
| AU745103B2 (en) | 2002-03-14 |
| WO2000012960A1 (en) | 2000-03-09 |
| JP2002523764A (en) | 2002-07-30 |
| CA2341166A1 (en) | 2000-03-09 |
| AU5694999A (en) | 2000-03-21 |
| KR20010072920A (en) | 2001-07-31 |
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